Stent for irrigation and delivery of medication

ABSTRACT

A stent comprises a flexible tube having a proximal end, a distal end, and a passageway extending from said proximal end toward said distal end. A first generally straight tube segment extends from the proximal end while a first generally curved segment extends from an end region of the first generally straight tube segment disposed away from the proximal end of the stent. A second generally straight tube segment extends from an end region of the first curved segment away from the first generally straight tube segment and is arranged at an acute angle relative to the first generally straight tube segment. A second generally curved tube segment extends from one end of the second generally straight tube segment and includes a channel on an exterior surface of the second generally curved tube segment. The first generally curved tube segment and the second generally straight tube segment further include at least one cavity irrigation hole extending from the tube passageway, for providing irrigation fluids into the cavity into which the stent is inserted. At least one segments includes a channel on an exterior surface. The channel is sized to serve as a reservoir to contain a predetermined amount of at least one form of medication for delivery, over a period of time, of the medication to a cavity region proximate which the stent has been inserted.

TECHNICAL FIELD

This application is a continuation of U.S. application Ser. No.11/511,876, filed on Aug. 29, 2006, which is hereby incorporated byreference in its entirety.

TECHNICAL FIELD

The present invention relates to tubes for medical applications and moreparticularly, to an intubation device for placement through the nasalairway into the sinus cavity or any other irregular cavity having anopening on one side, for treatment, irrigation and dispensing ofmedicine into the cavity.

BACKGROUND INFORMATION

Intubation devices, in general, are well known in the medical field.Tubes are often inserted into body passageways or cavities of a patientto ventilate, drain, irrigate and/or stent the cavity into which thetube in inserted. Continuing efforts are being made to design intubationdevices that are easily and comfortably inserted into a patient,particularly when the tube must be left in place within the patient. Italso becomes important to provide for a release of medication in a verycontrolled way in order to release a measured amount of activemedication on long term.

One medical use for an intubation device is in the pre and postoperative treatment of chronic rhinosinusitis (CRS). CRS is a disease ofthe nasal and paranasal sinuses characterized by symptoms of facialpain, nasal obstruction, and rhinorrhea. The treatment of CRS whetherpre-or post-operative, often requires the delivery of medication to themaxillary sinus area and other areas of the sinus cavity. In addition tothe delivery of medication, it is often desirable to have in place anintubation device for irrigation of the area.

There has been some attempt in the prior art to provide medication toremote, inaccessible areas. These include in bedding a product whichprogressively melts over a period of weeks or months. The problem whichsuch devices is that there melting process is influenced by the contactwith fluids and thus makes the delivery of medication unpredictable.

An additional problem is the desirability to keep a stent in place in acavity, such as the sinus cavity, over the course of several weeks ormonths in order to continue to be able to treat a particular area. Priorart devices were very difficult at the very least to keep in place.

Accordingly, what is needed is a stent which solves all of the foregoingproblems namely, which can deliver a precise amount of a specificmedication and/or irrigation fluids to a generally remote orinaccessible area over a long period of time; which by its shape isdesigned to stay in place in the cavity and which can keep open anydesired opening into a cavity.

SUMMARY

The present invention features a stent comprising a flexible tube havinga proximal end, a distal end, and a passageway extending from theproximal end to the distal end. A first generally straight tube segmentextends from the proximal end while a first generally curved segmentextends from an end region of the first generally straight tube segmentwhich is located away from the proximal end of the stent.

A second generally straight tube segment extends from an end region ofthe first curved segment away from the first generally straight tubesegment. The second generally straight tube segment is arranged at anacute angle relative to the first generally straight tube segment. Asecond generally curved tube segment extending from one end of thesecond generally straight tube segment. The second generally curved tubesegment includes a channel on an exterior surface which serves as areservoir for storing medication(s) to be delivered into the cavity overan extended period of time.

The first generally curved tube segment includes at least one holeextending from the passageway to an exterior surface of the firstgenerally curved tube segment. The second generally straight tubesegment may also include at least one hole extending from the passagewayto an exterior surface of the second generally straight tube segment.The hole in the second generally straight tube segment may have a largerdiameter than the hole in the first generally curved tube segment.

The second generally curved tube segment is comprised of a plurality ofstraight and curved tube segments. The second generally curved tubesegment may include a second generally curved tube portion, coupled to athird generally straight tube portion, coupled to a third generallycurved tube portion, coupled to a fourth generally straight tubeportion, coupled to a fourth generally curved tube portion, coupled to afifth generally straight tube portion, coupled to a fifth generallycurved tube portion.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other features and advantages of the present invention will bebetter understood by reading the following detailed description, takentogether with the drawings wherein:

FIG. 1 is a systematic side view of the stent according to the presentinvention;

FIG. 2 is a schematic front view of the stent according to the presentinvention;

FIG. 3 is a partial close of view of the second generally curved segmentof the stent according to the present invention; and

FIG. 4 is a schematic view of the stent of the present inventioninserted in the sinus cavity.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The present invention features a stent 10, FIG. 1, for a cavity havingan opening in at least one side, such as a nasal cavity. Although thepresent invention will be explained with regard to a nasal cavity, thisis not a limitation of the present invention as its use in any type ofcavity, whether regular or irregular, that has an opening in at leastone side is contemplated and can be achieved by someone skilled in theart. The stent according to the present invention features the abilityto remain in place long-term, serves as a support for the opening of thecavity and is able to deliver an active medication using the irrigationfeatures and the reservoir (storage) capabilities of the stent.

The stent 10 is comprised of a flexible hollow tube having a passagewayin the center of the tube and having a proximal end 12 and a distal end14. The stent is preferably made from a medical grade soft and resilientthermo-plastic material as is generally available for such products. Afirst generally straight tube segment 16 extends from the proximal end12. A first generally curved tube segment 18 extends from one end of thefirst generally straight tube segment 16 proximate and the end of thetube away from the proximal end 12 of the stent.

In the preferred embodiment, the first generally curved tube segment 18includes one or more holes 20 which extend from the interior passagewayof the stent 10 to the exterior surface of the first generally curvedtube segment 18. As will be explained in greater detail below, holes 20,if provided, serve to dispense medication and/or irrigation fluid whichis introduced into the passageway of the tube into one of the sinuscavities (if the present invention is disposed in a sinus cavity) or anyother cavity in which the stent according to the present invention isdisclosed.

Coupled to the first generally curved tube segment 18 is a secondgenerally straight tube segment 22. Tube segment 22 may also include, inthe preferred embodiment, one or more holes 20 which also serve todispense medication or irrigation fluid into the cavity into which thesegment is placed. The holes 20 may be all the same size or may differin size from tube segment to tube segment. In the present embodiment,the holes 20 are larger in the second straight segment 22 to favorirrigation in the cavity in which this portion is disposed. The lengthand the curvature of the first generally curved tube segment 18 is suchthat the second generally straight tube segment 22 is disposed at anacute angle 24 relative to the first generally straight tube segment 16.This orientation forms a narrowed passageway 26 between the firstgenerally straight tube segment 16 and the second generally curved tubesegment 28 which serves to hold or retain the stent in place when usedin the sinus cavity as will be explained in greater detail in FIG. 4below.

A second generally curved tube segment 28 is coupled to one end of thesecond generally straight tube section 22. The second generally curvedtube segment 28 is comprised of a number of smaller generally straightand or generally curved tube portions as will be explained below.

In the preferred embodiment, for example, the second generally curvedtube segment 28 may include a second generally curved tube portion 30,to which is coupled a third generally straight tube portion 32, coupledto a third generally curved tube portion 34 followed by a fourthgenerally straight tube portion 36, coupled to a fourth generally curvedtube portion 38 coupled to a fifth generally straight tube portion 40followed by a fifth generally curved tube portion 42. Theabove-mentioned combination of generally straight and generally curvedtube portions is not a limitation of the present invention however asany combination of curved and/or straight tube segments is contemplatedby the present invention.

The second generally curved tube segment 28 includes, on an exteriorsurface, a channel 44, FIG. 2, which serves to carry and dispensemedication which is introduced into the channel 44 prior to insertion ofthe stent into the patient.

It is contemplated that either the inserting physician or the stentmanufacturer will place the proper medication in this channel prior toinsertion of the stent into the patient or prior to the stent leavingthe manufacturer. For example, it may be desired to have a steroidmedication delivered to the patient over a period of time. Ananti-fungal medication may also be desired. The medication(s) will be ina form such that delivery of the medication(s) occurs over a generallypredetermined period of time. Such medications are well known in the artand include but are not limited to anti-fungal, antibiotics orantiseptic medication. Accordingly, the physician or pharmaceuticalcompany will place in the channel 44 the proper amount and type(s) ofdesired medication(s). The channel 44 and channel starting region 46,FIG. 3, will be collectively sized to hold the proper amount of desiredmedication(s). The channel will be as long, wide and deep as required tohold the amount of medication to be dispensed. The channel 44 may be onthe same side of the stent or may “spiral” around the exterior region ofthe stent.

The channel may be placed on any exterior surface of the stent. In thepresent embodiment, the channel 44 is on the side of the mucosa to betreated (the exterior part of the tube toward the side of the maxillarycavity). The groove or channel 44 has a volume formed by its with anddepth which forms in essence a reservoir having a capacity which may beadjusted to different volumes of medication(s) needed for long termdelivery of the desired medication(s).

The second generally curved tube segment 28 may include the channelstarting region in the shape of a hole or larger depression 46 whichextends inwardly from the exterior surface of the stent. In the presentembodiment, the channel starting region 46 is located in the secondgenerally curved tube portion 30.

The stent 10, FIG. 4 according to the present invention, may be insertedinto any cavity but functions particularly well when inserted throughthe middle meatus of patients which have already been operated on.Insertion of the stent 10 is easily accomplished given its flexible andpliable nature by physicians performing endoscopic surgery as suchinsertion of other items are presently accomplished by them and as iswell known to them.

One aspect of the present invention is the ability of the stent toremain in place. Fixation of the stent 10 is achieved by the “squeezing”effect between the first straight tube segment 16 and the secondgenerally curved tube portion 30. The acute angle formed between thefirst generally straight tube segment 16 and the second generallystraight tube segment 22 causes the stent 10 to curve back on itself andcreates a narrow channel 26 and causes the second generally curved tubeportion 32 push against the wall 50 of the sinus cavity. In addition,the segments 36, 38 and 40 (when applied in the sinus cavity) exert apressure by segment 42 against segment 32 to add to the squeezing effectat the channel or region 26.

In this manner, the stent according to the present invention can remainin place for extended periods of time to allow the sinus or other cavityto be irrigated and to allow the stent to deliver the desiredmedication(s) over extended periods of time and to keep open the sinuscavity's ostium by keeping it away from the surrounding structures(i.e., middle turbinate for the maxillary sinus ostium).

Accordingly, the present invention provides a novel and nonobvious stentwhich remains in place in a cavity and which may be used to delivervarious fluids to a remote area of the cavity using the hollowpassageway formed by the stent tube.

Modifications and substitutions by one of ordinary skill in the art areconsidered to be within the scope of the present invention, which is notto be limited except by the allowed claims and their legal equivalents.

1. An irrigation device comprising: a flexible tube having a proximalend, a distal end, and a passageway extending therethrough; a firstgenerally straight tube segment extending from the proximal end; a firstgenerally curved tube segment extending from an end of the firstgenerally straight tube segment; a second generally straight tubesegment extending from an end of the first generally curved tubesegment; and a second generally curved tube segment extending from anend of the second generally straight tube segment.
 2. The device ofclaim 1 wherein the flexible tube comprises a thermoplastic material. 3.The device of claim 1 further comprising one or more holes extendingfrom the passageway to an exterior surface of the flexible tube.
 4. Thedevice of claim 1 wherein the first generally curved tube segmentcomprises one or more holes extending from the passageway to an exteriorsurface of the flexible tube.
 5. The device of claim 1 wherein thesecond generally straight tube segment comprises one or more holesextending from the passageway to an exterior surface of the flexibletube.
 6. The device of claim 1 further comprising a channel on anexterior surface of the flexible tube.
 7. The device of claim 6 whereinthe channel comprises one or more medications.
 8. A method forirrigating a maxillary sinus cavity comprising: implanting at least aportion of a flexible tube in the maxillary sinus, wherein the flexibletube comprises a proximal end, a distal end, a passageway extendingtherethrough, a first generally straight tube segment extending from theproximal end, a first generally curved tube segment extending from anend of the first generally straight tube segment, a second generallystraight tube segment extending from an end of the first generallycurved tube segment, and a second generally curved tube segmentextending from an end of the second generally straight tube segment. 9.The method of claim 1 wherein the flexible tube comprises athermo-plastic material.
 10. The method of claim 1 wherein the flexibletube comprises one or more holes extending from the passageway to anexterior surface of the flexible tube.
 11. The method of claim 1 whereinthe first generally curved tube segment comprises one or more holesextending from the passageway to an exterior surface of the flexibletube.
 12. The method of claim 1 wherein the second generally straighttube segment comprises one or more holes extending from the passagewayto an exterior surface of the flexible tube.
 13. The method of claim 1wherein the flexible tube comprises a channel on an exterior surface ofthe flexible tube.
 14. The method of claim 13 wherein the channelcomprises one or more medications.